鉛(qian)是一種暗(an)灰色的金屬,熔點(dian)為327℃,它有(you)(you)很好的耐腐蝕(shi)性(xing)(xing)能(neng),常用來(lai)作硫(liu)(liu)酸(suan)設(she)備和管(guan)(guan)道(dao)襯里。鉛(qian)在(zai)大氣、淡水、海水中(zhong)很穩定,鉛(qian)對硫(liu)(liu)酸(suan)、磷酸(suan)、亞硫(liu)(liu)酸(suan)、鉻酸(suan)和氫氟酸(suan)等則有(you)(you)良好的耐蝕(shi)性(xing)(xing)。鉛(qian)不(bu)耐硝酸(suan)的腐蝕(shi),在(zai)鹽酸(suan)中(zhong)也(ye)不(bu)穩定。鉛(qian)質(zhi)軟,可(ke)塑(su)性(xing)(xing)好,管(guan)(guan)道(dao)工(gong)程中(zhong)常用鉛(qian)管(guan)(guan)。在(zai)安(an)裝鑄鐵管(guan)(guan)承插口(kou)時,常用鉛(qian)做接(jie)口(kou)填(tian)塞材(cai)料,以牌號(hao)為Pb6的鉛(qian)較(jiao)(jiao)適宜。硬鉛(qian)是鉛(qian)和銻的合金,它的抗腐蝕(shi)性(xing)(xing)略低于純鉛(qian),但機械強度(du)較(jiao)(jiao)高,常用于制造(zao)耐酸(suan)設(she)備。鉛(qian)蒸氣有(you)(you)毒,故熔化鉛(qian)時,要防止燙傷和鉛(qian)中(zhong)毒。在(zai)化工(gong)行(xing)業,鉛(qian)主(zhu)要用于處理硫(liu)(liu)酸(suan)的設(she)備上(shang)。Pb4用作設(she)備內(nei)襯,Pb6用作管(guan)(guan)道(dao)接(jie)頭,硬鉛(qian)可(ke)制造(zao)硫(liu)(liu)酸(suan)工(gong)業用的泵、閥門(men)、管(guan)(guan)道(dao)等。

